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We used flume experiments to study the effects of a temporary increase in stream flow on macroinvertebrates, leaf litter breakdown and soft-bodied benthic algae; both as a single stressor and eventually in combination with an increase in nutrient supply. In order to understand how well the flumes reflected the nearby stream ecosystem, we compared species composition of macroinvertebrates and benthic algae between the flumes and the nearby stream from which the flumes were supplied with water. As single stressors, nutrient addition and an increased flow velocity from 1.3 to 2.8 cm s−1 lead to an increase in the biomass of benthic algae, likely reflecting an improved transfer of nutrients into algal patches. However, the combined effect of flow and nutrient addition was smaller than the sum of both individual effects, likely because an increased biomass also was more susceptible to scouring. We found differences in macroinvertebrate and benthic algal taxon identity and abundance between stream and flumes. Since biodiversity is assumed to stabilize ecological functioning in response to disturbances and variation, we conclude that care should be taken in applying results from small scale experiments to stream ecosystems.

Presents a study analyzed factors associated with caregiver compliance and childhood immunization schedules in Bamenda, Cameroon. Significance of childhood immunizations in preventing disease; List of the variables found to be associated with increased likelihood of caregiver being up-to-date with childhood immunizations; Importance of health promotion programs in increasing the rate of immunizations.

Objective: A low expression of club cell secretory protein (CC16) and high levels of proinflammatory cytokines at preterm birth are associated with airway inflammation and more severe neonatal lung disease. The present study aimed to investigate if low levels of CC16, proinflammatory cytokines and vascular endothelial growth factors (VEGF) in tracheal aspirate early after birth were associated with lung function impairment at school age., Patients and Methods: Participants were 20 children, born very preterm (median gestational age 25+3 weeks+days, IQR: 24+1-27+0 weeks+days), who had tracheal aspirates collected during mechanical ventilation in their first day of life. CC16, cytokines, VEGF and matrix metalloproteinase-9 were measured in the tracheal aspirate and later correlated to results from advanced lung function measurements at 12 years of age., Results: Low levels of CC16 and high levels of the proinflammatory cytokines IL-1β and TNF-α in tracheal aspirate were associated with airway obstruction at school age but not with other lung function parameters. The correlation with airway obstruction was even stronger when the ratio between the respective proinflammatory cytokine and CC16 was used. In addition, low levels of VEGF and CC16 were associated with impaired diffusion capacity of the lung., Conclusions: An imbalance in inflammatory mediators and growth factors in the lungs at birth may have consequences for airway function and vasculature at school age in preterm born children., Competing Interests: Competing interests: CH has no conflict of interest. LB has received honoraria from Chiesi Pharma AB, Sweden, for being a member of the steering committee for the Nordic Neonatal Meetings and from AbbVie AB for lectures and for previously being a member of the steering committee for the NEOSPEX educational project. IHP holds stock/stock options in Premalux AB and has received honoraria from Baxter International for lectures. ET has received honoraria from Intramedic AB., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: Very preterm birth is associated with lung function impairment later in life, but several aspects have not been studied. We aimed to comprehensively assess lung function at school age in very preterm infants and term controls, with special emphasis on bronchopulmonary dysplasia (BPD), sex, and bronchodilator response., Methods: At 12 years of age, 136 children born very preterm (85 with and 51 without BPD) and 56 children born at term performed spirometry, body plethysmography, impulse oscillometry, measurement of diffusion capacity, and multiple breath washout, before and after bronchodilator inhalation., Results: Airway symptoms and a diagnosis of asthma were more common in children born very preterm. These children had more airflow limitation, seen as lower forced expiratory volume in 1 s (FEV 1 ) (p < .001), FEV 1 /forced vital capacity (FVC) (p = .011), and mean forced expiratory flow between 25% and 75% of FVC (p < .001), and a higher total and peripheral airway resistance compared with term-born controls. There was no difference in total lung capacity but air trapping and lung clearance index were higher in children born very preterm. Diffusion capacity was lower in children born very preterm, especially in those with a diagnosis of BPD. In most other tests, the differences between preterm-born children with or without BPD were smaller than between children born preterm versus at term. Boys born preterm had more lung function deficits than preterm-born girls. In children born very preterm, airway obstruction was to a large extent reversible., Conclusion: At 12 years of age, children born very preterm had lower lung function than children born at term in most aspects and there was only little difference between children with or without BPD. Airway obstruction improved markedly after bronchodilator inhalation., (© 2023 The Authors. Pediatric Pulmonology published by Wiley Periodicals LLC.)

Aim: Very preterm birth may be associated with lung function impairment later in life. It is not known if this is caused by prematurity per se or by associated perinatal events, such as maternal-foetal inflammation and severity of early neonatal lung disease. We assessed these factors in a prospective cohort of very preterm infants followed from birth to middle school age., Methods: In 71 infants with a gestational age of median 27.4 (range 23.9-31.7) weeks, pro-inflammatory and modulatory cytokines were measured in umbilical cord blood and in arterial blood sampled at 6, 24 and 72 h after birth, and cumulated cytokine concentrations were calculated as area under the curve (AUC). At median 12.6 (range 12.3-13.5) years of age, pulmonary function testing was done in 53 children., Results: There was a positive correlation between days on mechanical ventilation and AUC for IL-6 (p = 0.001), IL-8 (p = 0.015) and IL-10 (p = 0.006). Infants with bronchopulmonary dysplasia (BPD; n = 32) had higher AUC for the cytokines IL-6, IL-8 and IL-10 than those without BPD (all p < 0.01). Higher levels of AUC for IL-6 at birth correlated with lower forced expiratory volume in 1 s (p = 0.030) and lower mean expiratory flow rate between 25 and 75% of forced vital capacity (p = 0.034)., Conclusion: Perinatal inflammation, assessed by circulating cytokines in the first three days of life, was associated with BPD and with airway obstruction at 12 years of age., (©2021 The Authors. Acta Paediatrica published by John Wiley & Sons Ltd on behalf of Foundation Acta Paediatrica.)

Background: Club cell secretory protein (CC16) probably has a role in protecting the lung from inflammation., Aim: To evaluate if low levels of CC16 in gastric fluid at birth, reflecting low levels of CC16 in the lung, would be associated with lung inflammation and respiratory morbidity., Methods: A study of 64 infants with mean gestational age 26.1 weeks. CC16 was analyzed in gastric fluid at birth. CC16, pro-inflammatory cytokines, and MMP-9 were analyzed in tracheal aspirate within 24 h from birth., Results: CC16 in gastric fluid increased with gestational age (P = 0.033). Lower concentrations of CC16 in gastric fluid at birth were associated with higher concentrations of IL-1β (P = 0.028), TNF-α (P = 0.034), and MMP-9 (P = 0.015) in tracheal aspirate. Infants who needed mechanical ventilation at 24 and 72 h of age had lower CC16 in gastric fluid than those not ventilated at these ages (P = 0.011 and P = 0.024, respectively). Lower CC16 in gastric fluid was associated with higher FiO 2 at 6 h (P = 0.009), higher PaCO 2 at 24 h (P = 0.03), more ventilator days (P = 0.012) and more days with supplemental oxygen (P = 0.03). Infants who had either died or were still treated with supplemental oxygen at 36 weeks postmenstrual age had lower CC16 in gastric fluid than infants with none of these outcomes (P = 0.049)., Conclusion: A low CC16 concentration in gastric fluid at birth was associated with increased inflammation in the trachea within the first 24 h of life and with more need for respiratory support in the neonatal period., (© 2018 Wiley Periodicals, Inc.)

Introduction: The respiratory movement measuring instrument (RMMI) is a laser-based non-invasive technique to measure breathing patterns and respiratory movements (RMs). Little knowledge is known about the ability of the RMMI to measure breathing patterns and the correlation between RMs and breathing volumes., Objectives: One aim was to investigate whether the RMMI could discriminate between normal versus abdominal versus high costal breathing patterns in different body positions. A second aim was to determine the correlation between RMs and breathing volumes in different body positions., Method: Twenty adult, healthy subjects (10 women) were included in the study. The RMMI was used to study the above-mentioned breathing patterns in supine, sitting and standing positions. A subgroup of 12 subjects (6 women) simultaneously performed measurements of breathing volumes while RMs were recorded., Results: The RMMI was able to discriminate between different breathing patterns in different body positions (P<0·001). The upper thoracic contribution to RMs in the sitting position was 47% for natural breathing, 32% for abdominal breathing and 64% for high costal breathing; similar results were found in the supine and standing positions. A strong correlation was observed between RMs as measured by the RMMI and different breathing volumes in all three body positions (Spearman's rho 0·86-1·00)., Conclusion: The RMMI can be used to measure and analyse different breathing patterns in different body positions, and the correlation between measured RMs and breathing volumes is strong., (© 2015 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.)

Alveolar capillary dysplasia with misalignment of pulmonary veins (ACD/MPV) is a rare and lethal developmental disorder of the lung defined by a constellation of characteristic histopathological features. Nonpulmonary anomalies involving organs of gastrointestinal, cardiovascular, and genitourinary systems have been identified in approximately 80% of patients with ACD/MPV. We have collected DNA and pathological samples from more than 90 infants with ACD/MPV and their family members. Since the publication of our initial report of four point mutations and 10 deletions, we have identified an additional 38 novel nonsynonymous mutations of FOXF1 (nine nonsense, seven frameshift, one inframe deletion, 20 missense, and one no stop). This report represents an up to date list of all known FOXF1 mutations to the best of our knowledge. Majority of the cases are sporadic. We report four familial cases of which three show maternal inheritance, consistent with paternal imprinting of the gene. Twenty five mutations (60%) are located within the putative DNA-binding domain, indicating its plausible role in FOXF1 function. Five mutations map to the second exon. We identified two additional genic and eight genomic deletions upstream to FOXF1. These results corroborate and extend our previous observations and further establish involvement of FOXF1 in ACD/MPV and lung organogenesis., (© 2013 Wiley Periodicals, Inc.)

Introduction: The term dysfunctional breathing (DB) has been introduced to describe patients who display divergent breathing patterns and have breathing problems that cannot be attributed to a specific medical diagnosis. Patients with DB are often misdiagnosed as having asthma., Objectives: To describe patients with DB, five years after a breathing retraining intervention., Methods: Out of initially 25 patients with DB and 25 age and sex-matched patients with asthma, 22 patients with DB and 23 patients with asthma (ages 25-78 years) were followed up after five years. Data were collected from posted self-report questionnaires. Only patients with DB had received breathing retraining, consisting of information, advice and diaphragmatic breathing. Patients were evaluated regarding quality of life (SF-36), anxiety, depression, sense of coherence, hyperventilation, influence on daily life, emergency room (ER) visits, and symptoms associated with DB., Results: Quality of life (SF-36), physical component summary scale (PCS), had improved in patients with DB from 43 to 47 (p = 0.03). The number of ER visits had decreased from 18 to 2 in patients with DB (p = 0.02). Symptoms associated with DB had decreased extensively, from a mean score of 6.9 to 2.7, on a DB criterion list (p < 0.001). Patients with DB were less impaired by their breathing problems both in daily life and when exercising (p < 0.001). The only difference found over time in the asthma group concerned quality of health, bodily pain, which had deteriorated, from 77 to 68 (p = 0.049)., Conclusion: This five-year follow-up study indicates that patients with dysfunctional breathing benefit from breathing retraining., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Introduction: The term dysfunctional breathing (DB) has been introduced to describe patients who display a divergent breathing pattern and have breathing problems that cannot be attributed to a specific medical diagnosis such as asthma, chronic obstructive pulmonary disease or sensory hyper-reactivity., Objective: The objective of this study was to investigate similarities and differences in patients with DB, and patients with well-controlled asthma regarding health-related quality of life, anxiety, depression, sense of coherence (SOC), hyperventilation and effects on daily life., Methods: Twenty-five consecutive patients with DB, and 25 age- and sex-matched patients with asthma (ages 20-73 years) participated in the study. The diagnosis of DB was based on the presence of a dysfunctional breathing pattern and at least five symptoms associated with DB., Results: The group with DB had lower health-related quality of life (short form 36): vitality (mean) 47 vs 62, social functioning 70 vs 94 and role emotional 64 vs 94 (P < 0.05) than the asthmatic group. The DB group also had a higher prevalence of anxiety (56% vs 24%) and a lower SOC (134 vs 156) (P < 0.05). Hyperventilation, defined according to the Nijmegen symptoms questionnaire, was observed in 56% of patients with DB vs 20% in the asthma group (P = 0.02)., Conclusions: The results of the study indicate that patients with DB are more disabled than patients with well-controlled asthma. There is a great need for more knowledge about breathing symptoms of a dysfunctional nature, to be able to identify and manage these patients adequately.

The development of a quantification method for monoclonal antibodies in serum has been accomplished by high-performance liquid chromatography multiple reactions monitoring mass spectrometry. A human monoclonal antibody (HmAb) was used as the model protein for method development and validation. A peptide from the CDR3-region of its heavy chain was selected and used for quantifying the entire mAb. This signature peptide served as a template for the internal standard. Prior to mass spectrometric analysis approximately 50% of the total serum protein content was removed by albumin depletion. The accuracy of the method ranged between 99 and 112% in cynomolgus monkey serum. The intra-assay coefficient of variation (CV) was lower than 4% at 4 microg/mL and 200 microg/mL HmAb (n = 3). The CV at 400 microg/mL corresponded to 9% (n = 3). In addition, the interassay variation was investigated in a male cynomolgus serum pool and in a female cynomolgus serum pool. The CV for the male cynomolgus pool at 4 microg/mL HmAb was 7% (n = 3). The CV obtained from the female pool was 8% (n = 3), at 4 microg/mL. The dynamic range of the method was 3 orders of magnitude. After albumin depletion of 25 microL of serum, a lowest limit of quantification of 2 microg/mL HmAb was reached in both human and cynomolgus monkey samples.

Objective: HIV-associated diarrhoea occurs in nearly all patients with acquired immunodeficiency syndrome (AIDS) in the developing countries. Diarrhoea is caused by the HIV-related immune dysfunction and is pivotal in the decrease of the helper T-cell (CD4 + ) population. Enteric pathogens in HIV-associated diarrhoea are, for example, Cryptosporidium, Amoeba and Campylobacter species. Bovine colostrum is the first milk the suckling calf receives from the cow. It is rich in immunoglobulins, growth factors, antibacterial peptides and nutrients. It supplies the calf with a passive immunity before its own active immunity is established. ColoPlus is a product based on bovine colostrum and is designed for slow passage through the gastrointestinal tract, as well as having a high nutritional value. The aim of the study was to investigate whether ColoPlus given orally can influence the severe diarrhoea associated with HIV infection., Material and Methods: The study was carried out at Braithwaite Memorial Specialist Hospital, Port Harcourt, Nigeria. Thirty patients with HIV-associated diarrhoea were included in the study. The patients were treated with ColoPlus for 4 weeks in an open-labelled non-randomized study, after an observational period of one week. After a post-treatment period of another two weeks, treatment with anti-HIV drugs was started, if deemed appropriate. The effects on the frequency of stool evacuations per day, on body-weight, fatigue, haemoglobin levels and CD4+ counts before (week 1) and after treatment with ColoPlus (week 7) were measured., Results: There was a dramatic decrease in stool evacuations per day from 7.0+/-2.7 to 1.3+/-0.5 (+/-SD), a substantial decrease in self-estimated fatigue of 81%, an increase in body-weight of 7.3 kg per patient and an increase in CD4+ count by 125%., Conclusion: ColoPlus may be an important alternative or additional treatment in HIV-associated diarrhoea.

Information about protein conformation can be obtained with hydrogen/deuterium exchange (HDX) mass spectrometry. The isotopic solution-phase exchange of specific amide hydrogen atoms can be followed using low-vacuum nozzle-skimmer collision-induced dissociation (CID). In this study, the nozzle-skimmer technique was complemented by electron capture dissociation (ECD) Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS). The solution-phase exchange at a specific residue is monitored by comparing isotopic distributions of two consecutive b- or c-type ions. While nozzle-skimmer fragmentation takes place in the low-vacuum region of the mass spectrometer, ECD occurs at ultra-high vacuum within the mass analyzer cell of the FTICR mass spectrometer. The dissociations take place at 10(-4) and 10(-9) mbar, respectively. Low-vacuum nozzle-skimmer fragmentation can result in intramolecular exchange between product ions and solvent molecules in the gas phase. Consequently, the solution-phase information about protein or peptide conformation is lost. It was not possible to monitor isotopic solution-phase exchange at the eighth residue in substance P, (Phe)8, with nozzle-skimmer CID. By using the in-cell ECD fragmentation method, the solution-phase exchange at the (Phe)8 residue was preserved during mass spectrometric analysis. This result shows the complementary aspects of applying fragmentation at low and at high vacuum, when studying isotopic exchange in solution at specific residues using FTICRMS., (Copyright 2006 John Wiley & Sons, Ltd.)

The difficulty with integrating solution-phase hydrogen/deuterium exchange (HDX) and tandem mass spectrometry is that the energy added to cause fragmentation might promote gas-phase migration of the added deuterium atoms. Here, we compare the solution-phase HDX profiles generated from a- b- and y-type fragment ion series originating from capillary-skimmer dissociation. The isotopic distributions of fragments from the different fragment ion types were used to determine the isotopic state of the amide hydrogen within a specific residue. Even though the same amide hydrogen was examined, the result was different for different fragment ion types. This observation indicates that different fragment series are not equally subjected to inter-molecular migration during collision-induced dissociation (CID). We also investigated the gas-phase reactivity of originally undeuterated CID fragments of penta-phenylalanine using gas-phase HDX in an external accumulation hexapole. The incorporation of deuterium into the different fragments was studied as a function of hexapole pressure. It was found that different b- and y-ions from the same peptide had different gas-phase reactivity. However, the a-ions did not display significant gas-phase reactivity. The observed behavior has significant impact on any method that involves comparing the isotopic distributions of different fragment ions. Great care has to be taken in the interpretation of the HDX data using CID to increase the spatial resolution. The isotopic state observed after solution-phase exchange might be more preserved for some CID-fragment types.

Liquid chromatography mass spectrometry (LC-MS) is a valuable tool in the analysis of proteins and peptides. The combination of LC-MS with different fragmentation methods provides sequence information on components in complex mixtures. In this work, on-line packed capillary LC electrospray ionization Fourier transform ion cyclotron resonance MS was combined with two complementary fragmentation techniques, i.e. nozzle-skimmer fragmentation and electron capture dissociation, for the determination of hormonal peptides in an acid ethanol extract of mouse pancreatic islets. The most abundant peptides, those derived from proinsulin and proglucagon, were identified by their masses and additional sequence-tag information established their identities. Interestingly, the experiments demonstrated the presence of truncated C-peptides, des-(25-29)-C-peptide and des-(27-31)-C-peptide. These novel findings clearly illustrate the potential usefulness of the described technique for on-line sequencing and characterization of peptides in tissue extracts.

A new method is presented to accurately determine the probability of having a deuterium or hydrogen atom on a specific amide position within a peptide after deuterium/hydrogen (D/H) exchange in solution. Amide hydrogen exchange has been proven to be a sensitive probe for studying protein structures and structural dynamics. At the same time, mass spectrometry in combination with physical fragmentation methods is commonly used to sequence proteins based on an amino acid residue specific mass analysis. In the present study it is demonstrated that the isotopic patterns of a series of peptide fragment ions obtained with capillary-skimmer dissociation, as observed with a 9.4 T Fourier transform ion cyclotron resonance (FTICR) mass spectrometer, can be used to calculate the isotopic state of specific amide hydrogens. This calculation is based on the experimentally observed isotopic patterns of two consecutive fragments and on the isotopic binomial distributions of the atoms in the residue constituting the difference between these two consecutive fragments. The applicability of the method is demonstrated by following the sequence-specific D/H exchange rate in solution of single amide hydrogens within some peptides., (Copyright 2000 John Wiley & Sons, Ltd.)